package com.example.blog.mapper;import com.example.blog.entity.UserInfo;import com.example.blog.entity.ViewObject.UserInfoVo;import org.apache.ibatis.annotations.Mapper;import org.apache.ibatis.annotations.Param;@Mapperpublic interface UserMapper {    int userReg(UserInfo user);    UserInfo getUserByUsername(@Param("username") String username);    UserInfo getUserById(@Param("userid") Integer userid);}